Create random loading message generator

Add a service responsible of giving random loading messages, and apply
it in the fadingText directive that is inside of the practice template
Take out question list component.
Hide some practice elements while practice content load.
Merge pull request #24 from mlopez-firstfactory/master

Create random loading message generator
Fix fadingText, we can't pass values directly

Add a variable containing the desired message, and pass it to the
directive instead of giving it a raw value.
Create and integrate new directive for splash messages.
Add new style for progress bar loading messages.
*Fix user Run Out of questions method.
Rename Messages service to a more specific name(splash messages)
Move Splash Messages services from application.services to practice.services.
Add responsive classes to numeral loading directive

*It was missing a couple of parameters.
Merge pull request #25 from mlopez-firstfactory/master

Fix fadingText, we can't pass values directly
Add display “Custom Practice” on the left nav menu above “Group practice”.
Add display “Take a Full Length Test” on the left nav menu below “Group Practice”
Add responsive classes for loading message
Merge branch 'master' of https://github.com/joanrm20/maua
Merge pull request #54 from joanrm20/master

Maua client new features and fixes